1. Field of the Invention
The present invention generally relates to image forming apparatuses, imaging process units, and methods for recording information concerning the image process units, in particular to an image forming apparatus detachably connectable to an imaging process unit, an imaging process unit possible to be mounted to the image forming apparatus, and a method for recording information concerning the image process unit in the image forming apparatus.
2. Description of the Related Art
Recently, there are many cases in that an IC (Integrated Circuit) tag is mounted to a process cartridge (imaging process unit) which configures an imaging unit forming a visualized image onto a photoreceptor of a copier and is easily detachable from a main unit. The IC tag not only reads out data (for example, an ID) but also accumulates a process condition, a use history, a defect history, a use environment, and a like.
For example, Japanese Laid-open Patent Application No. 2002-014576 discloses the invention related to an image forming apparatus including a control circuit for writing and reading data such as the use history, the process condition, and the like to/from a non-volatile memory mounted in the process cartridge detachably connected to the image forming apparatus. In the image forming apparatus, an encrypted text is generated by using an original document data and an encryption key in that the encryption key is generated based on data (special value for each unit) from a control circuit which does not generate the encryption key.
However, in the invention described in Japanese Laid-open Patent No. 2002-014576, only an encryption between the main unit and a printer is disclosed but data to write to the non-volatile memory are not considered. That is, in a case in that a third party extracts the process cartridge, data maintained in the non-volatile memory of the process cartridge may be leaked to an outsider and may be reused after the data are falsified.
However, in a case in that the process cartridge is distributed for a recycle or a like, the data in the non-volatile memory is easily read out and private data and a like can be leaked. In addition, if a malicious agent or a like intervenes for the recycle, product life data or a like recorded in the process cartridge may be falsified and may be sold in the disguise of a new process.